langcodes is a toolkit for working with and comparing the standardized codes
for languages, such as ‘en’ for English, ‘es’ for Spanish, and ‘zh-Hant’ for
Traditional Chinese. These are BCP 47 language codes, formerly known as ISO
language codes.

langcodes is designed for Python 3, but this version of langcodes,
‘langcodes-py2’, is a backport to Python 2.7.